1. Field of the Invention
The present invention relates to an optical unit assembly including an optical system, an image reader for optically reading a document image and an image forming apparatus provided with an image reader.
2. Description of the Related Art
Generally, an image reader optically reads a document by irradiating the document placed on a document placement surface with light from a light source via a lens or the like and receiving the reflected light from the document by means of image pickup elements such as CCDs (Charge Coupled Devices). An optical unit containing the light source, the lens, the CCDs and the like in a casing is generally accommodated in a box-shaped image reader frame having the document placement surface.
If the above optical unit is installed oblique to the document placement surface in the image reader constructed as above, there might be a defect in a read image. Accordingly, such an inclination is solved by adjusting the height of the casing of the optical unit with respect to the image reader frame.
As a mechanism for adjusting the above inclination, a construction in which a stepped inclination adjusting member is slidably arranged between a casing of an optical unit and an image reader frame to support the casing of the optical unit is proposed in Japanese Unexamined Patent Publication No. 2004-274651. With this proposed technology, the position of the step supporting the casing of the optical unit is changed by horizontally sliding the inclination adjusting member, whereby the inclination of the optical unit can be adjusted.
However, the technology of Japanese Unexamined Patent Publication No. 2004-274651 presumes to solve the inclination of the optical unit upon assembling the optical unit into the image reader frame, and it is difficult to adjust the inclination once the optical unit is assembled. In other words, there has been a problem of being unable to change the position of the inclination adjusting member afterward since the inclination adjusting member is fixed at a specified position of the image reader after being slid during the assembling.